"I am to Simone de Beauvoir what Horrible Histories are to Simon Schama," says Bridget Christie. It's true, and it's a breakthrough for this always endearing but until now often frivolous comic. Christie made her name in sub-surrealist comedy – making a point came a distant second to dressing as an ant or driving a shopping-trolley Popemobile. But now, as fans of her Radio 4 series Bridget Christie Minds the Gap will know, Christie has outed herself as a feminist. Her new show is by far her most satisfying, a clownish but unmistakably committed attack on sexism, and an exploration of how best to tackle it.

At its richest, it deploys Christie's lateral brand of humour to score feminist points in the most unexpected ways. The opening gag, about women being good for nothing but turning in circles, delivers more than it promises. A routine about a recent sexist remark by ex-racing driver Stirling Moss concludes with a fantasy sequence imagining Moss's funeral – a vision of scantily-clad men with spunking champagne bottles that luridly sends up the chauvinism of Formula One. More straightforwardly, she skewers the so-called Bic for Her pen with a ridiculous mime of her struggle to operate a non-gender-specific ballpoint.

To the point … A Bic for Her. Photograph: Murdo Macleod Murdo Macleod/Murdo Macleod

It's not always successful: there's a sense that Christie is still discovering how best to combine comedy and ideological conviction. Her instinct is to clown around and self-deprecate, which is consistently funny, but too often makes her fury the butt of the joke, rather than the sexism that provokes it. The later sections – particularly one about rearranging the lads' mags displays in newsagents – go lighter on the goofiness, but also on the laughs. But that's easy to forgive, as Christie works out all at once how to respond to such casual and public denigration of women, and how to be funny about it. Her enquiry has produced a fine show, which piles derision and tomfoolery upon everyday sexism, while never pretending that jokes alone will solve the problem.

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